GB2179271A - An adhesive sheet for prevention against aquatic growths and a method for sticking the adhesive sheet - Google Patents

Description

1 GB 2 179 271 A 1

SPECIFICATION

An adhesive sheet for prevention against aquatic growths and a method for sticking the adhesive sheet The present invention relates to an adhesive sheet for prevention against aquatic growths such as an ima Is and 5 plants which wi I I attach and propagate on the surface of ships and other structures in contact with water.

Usually, on the surface of ships and other underwater structures, animals such as barnacles, mussels oysters and pea rl-oysters, as wel I as plants such as various kinds of seaweedswil I attach and propagate to produce a bad inf I uence on navigation amongst others, so that various means are taken to preventthe adhesion and propagation of these animals and plants. For example, there is a method to apply paint 10 containing a poisonous substance dissolving a very smal I amount thereof in seawater, however the paint must be recoated every l to 2 years to continue the effect of preventing the adhesion. Also, a method for preventing the adhesion of noxious a nima Is and plants by using copperplate is known, however, since chemical reactions between copper and seawaterwil l proceed comparatively rapidly, there is a problem on durabi l ityun less fairly thick copperplate is used. Thus this method is not practical.

The inventors devoted themselves to study these problems, wherein copper is alloyed tom in imize the dissolving out of copper ions into seawater and with copper a l loy plate to withstand the corrosion due to seawater fora long period, as well as to simplify the enforcement onto the underwater structures, thus to complete an adhesive sheet for prevention against aquatic growths with excellent durability.

In the present invention, one surface of copper-nickel a l loy plate with a weight ratio of copper to nickel of 20 100:0 to 80:20, is provided with a pre-determined pressure sensitive adhesive layer, existing on a special primer layer, so that this sheet will prevent the adhesion and propagation of aquatic growth, and yetthe dissolving out of copper ions into seawater is minimized as well as the enforcement being made easy and the sheet is durable for use over along period of time.

Figure 1 is a perspective view showing apart of an adhesive sheet for prevention against aquatic growth 25 according to the present invention.

Figure 2 is a sectional view of Figure 1.

The adhesive sheet (6) for prevention against aquatic growths is based on copper: nickel alloy plate as a base material (1), with a ratio of coppernickel of 100:0 to 80:20 by weight; one surface of which is primertreated to form a special primer layer (2), on which primer layer a pressure sensitive adhesive layer (3) having waterproof W and weatherproof properties is provided in a required thickness, and on which pressure sensitive adhesive layer, a release paper (4) is attached as the occasion demands.

If thethickness of copper-nickel alloy plate forming the base material is more than 0.05mm, the plate is stable in its strength and able to be used. The durable years of the plate are proportional to its thicknessjor instance: the durable years of alloy plate of about 0. 1 mm thick, of which the copper: nickel ratio is 90: 10, are 35 about 5 to 10 years. In the case where the content of copper in the alloy is 100%, the melting speed of copper ions in seawater is large, and the effect of prevention against aquatic growth is excellent, however, the durable years thereof are comparatively shorterthan those containing a predetermined quantity of nickel.

The primer layer contains as the main materials, elastomer, tackifier resin, epoxy resin and curing agent of epoxy resin, and as the occasion demands, anti-injurious agents of copperfor a pressure sensitive adhesive 40 and anti-aging agents are added, these components are mixed in their necessary quantities and melted into a mixture of a single or more than two kinds of organic solvents, such as toluene, ethyl acetate, methyl ethyl ketone, acetone and isopropanol to form an about 1 to 50% (weight %) solution, and are painted on a necessary surface of base material so as to become a solid part of about 1 to 20 g/M2, preferably about 3 to 10 g/M2, thus the required primer layer is formed. As the elastomers, there are, for example, epoxy modified natural rubber, 45 (modified) methyl methacrylate grafted natural rubber, styrenebutadiene rubber, nitrile rubber, chlorinated rubber and their modified rubbers. And, as the tackifier resin, there are, for example, those named as tackifier resin in the pressure sensitive adhesive layer component and phenol resin. And, as the epoxy resin, there are, for example, polyfunctional epoxy compounds such as ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,6-hexanediol cliglycidyl ether, and as the curing agentforthese epoxy resins, there are 50 polyamines such as diethylene triamine, triethylene tetramine, diethyl aminopropylamine, polyamides such as "Varsamid 110% "Varsamid 125% "Varsamid 14W sold by the General Mills Company, and " LancastA" sold by the Ciba-Geigy Company, polycarboxylic anhydride such as phthalic anhydride, dodecyl succinic anhydride, methyinadic anhydride, methyl tetrahydro phthalic anhydride, polysulfide, polymercaptan, dicyandiamine, resol type or novolaktype phenol resin, and imidazole compounds such as 2-ethyi-4-m ethyl 55 imidazole, 1 -cyanoethyl-2-phenyl imidazole, and these compounds are blended to a polyepoxy compound with an epoxy equivalent.

The blending ratio of the elastomer, tackifier resin and epoxy resin which are forming the primer layer is exemplified in that 100 weight parts of elastomer, 20 to 300 weight parts of tackifier resin and 30 to 200weight parts of epoxy resin are blended, to which a curing agent corresponding to an epoxy equivalent is blended. For 60 the antioxidant to be blended in the primer layer, the same substance blended to pressure sensitive adhesive may be used, and the blending quantity is about 0.5 to 5 weight parts to 100 weight parts of eiastomer. And, as anti-injurious agents of copper, there are, for example, N-isopropyl -N'- phenyl-P-phenylene diamine, N,W-diphenyl-P-phenylene diamine, N,N'-di-2-naphthyl-P-phenylene diamine, and their blending quantity is about 0.1 to 3 weight parts to 100 weight parts of elastomer.

2 GB 2 179 271A 1 2 The pressure sensitive adhesive layerisformed of elastomer, tackifier resin, vulcanizing agent, antioxidant asthe main materials, and the thickness of the layeris about20to 1000 p,, preferablyabout 100to400 Ii. The formation of a pressure sensitive adhesive layerismore preferablya solventless system, because, byrneans of a solventsystem, residual solventwhich requires much time for drying, mayexerta bad influence uponthe 5 durability.

The pressure sensitive adhesive layeris particularly preferably a cross linking typeto obtain durabilityfora long time. As the elastomer componentforming the pressure sensitive adhesive layer,there arethosehaving weatherabiiity and waterproof properties,such as natural rubber, modified methyl methacryiate grafted natural rubber, polyisobutylene rubber, butyl rubber, styrene-butadiene rubber, styreneisoprene-styrene block copolymer rubber, styrene-ethylene-butylene-styrene block copolymer rubber, reclaimed natural 10 rubberand reclaimed butyl rubber.

Asthetackifier resin,there are poiyterpene resin,terpene phenol resin, resins ofthe rosin group, resinsof the rosin estergroup andtheir hydrogenerated resins, and petroleum resins such as C5series petroleum resins, C5to C9 copolymerised series resins, C9series petroleum resinsand their hydrogenerated resins, and in casethe property of long period weatherabilityis needed, hydrogenated resins are particularly preferable. 15 As the vulcanizing agent and auxiliary agentof vulcanization which are addedfor makingthe pressure sensitive adhesive into a cross linking structure,there are a resin type such as reactive phenol resin and a sulphurtype. Tothe pressure sensitive adhesive, fillers such as clay, zincwhite, calcium carbonate, magnesium carbonate, carbon black, silicate areadded to promote the vulcanizing effectand aswell weighting and reinforcement effects may be achieved. As an antioxidant, those with amine groups, alkyl phenol groups,thiourea groups or benzimidazol groups may be suitably used.

The pressure sensitive adhesive sheet of the present invention,which isformed as above mentioned, isfor instance, when this sheet isstuckon the hull of afibre reinforced plasticvessel such as a yacht,the portion of the hull wherethe sheetisto bestuck, is preliminarily cleaned in a suitable mannerto fully remove contamination which is harmful forthe adhesion of adhesive so asto cause no clearance between the pressure 25 sensitive adhesive sheets, thus to strongly press the sheets to be closely contacted without having a bubble between the sticking surface of the hull and the adhesive sheet. In this case, if the sticking surface of the pressure sensitive adhesive sheet is preliminarily primer processed, much stronger adhesion maybe effected. This primer layer is effected by using a primer solution applied to the surface of the base material and is similarly processed to form the necessary primer layer.

Some preferred embodiments will be given in the following.

Example 1

Raw material having the following blending ratio was put into an enameled containerand mixed bystirring 35 for about 5 hours to obtain a primer solution.

Heveaplus Mg - 30' 1009 Arkon p_1002 100g Epicoate 828 3 125 g Epicure DX1 03 4 75g 40 Sumilizer MDP5 1 g Nocracwhite 6 0.5 g Toluene 450 g Methyl ethyl ketone 450 g 45 so 3 4 Commodity name of natural rubber grafted with 30% methyl methacrylate made by]TO SH0J1 COMPANY LIMITED.

2 Commodity name of a hydrogenated petroleum resin (softening point 1 00'C) made byARAKAWA CHEMICAL INDUSTRIES, LIMITED.

Commodity name of a polyepoxy compound made by UKA SHELL EPOXY K.K.

Commodity name of a curing agent of epoxy resin made by Uka Shell Epoxy Kabushiki Kaisha Commodity name of a bisphenol group anti-oxidant made bySumitomo Chemical Company Limited.

6 Commodity name of an amine group anti-oxidant made by OUCHI-SHINKO CHEMICAL INDUSTRY CO. LTD.

The above mentioned primersolution was applied on one surface of a coppernickel alloy plate with a copper-nickel weight ratio of 90:10, having width 40Omm x length 1 Om xthickness 0,1 mm, then a pressure sensitive adhesive layer of the following composition was applied on the primer layer by a calender roll so that 60 its thickness became 150I.L (microns), a release paper was stuck on the pressure sensitive adhesive layer, and the thus obtained adhesive sheet was coiled round on a paper tube of about 3 inch bore to obtain a pressure sensitive adhesive sheet for prevention against aquatic growths according to the present invention. 180'peel adhesion to a fibre reinforced plastic plate (FRP) of 3mm thickness of the obtained adhesive sheet was 2.6 kg/25mm (measuring temperature 23'C, 65% relative humidity), the primer solution was applied on a FRP plate65 j 3 GB 2 179 271 A 3 of 3mm thickness so that the painted amount after drying became 4 to 6g/M2, and 180' peel adhesion of the adhesive sheet to this primer layer forming surface was 7.5 kg/25m m, and due to the formation of the primer layer, the adhesion and the durabi I ity between the alloy plate base material and the adhesive agent is stabi I ized and as well the adhesion between the adherent and adhesive agent can be remarkedly improved.

5 Blending of adhesive agent:

Natural rubber (smoke coat) 100 parts (weight) Calcium carbonate 70 parts (weight) Zincwhite 30 parts (weight) Carbon black 3 parts (weight) 10 Super ester L 7 30 parts (weight) Process oi 1 10 parts (weight) Arkon P 100 2 100 parts (weight) Alkyl phenol disuifide 5 parts (weight) Dibutyiditho zinecarbamate 1 parts (weight) 15 SumilizerMDP5 3 parts (weight) 7 - Commodity name of a liquid rosinester resin made byARAKAWA CHEMICAL INDUSTRIES, LIMITED.

2, 5 - cf. above mentioned primer blending Afterthe primer liquid was applied so that on both of the inside and outside surfaces of FRP plate of length 20 30Omm xwidth 21 Omm x thickness 3mm, the applying amount after drying becomes 4 to 6 g/M2, theadhesive sheet of the present invention was stuck on the primer layer of both inside and outside surfaces, the plate was suspended at 1 mm underthe water level of seawater introduced in the laboratory of our company for one year and the condition of adhesion of aquatic growths was observed. As a result, afterthe lapse of one year,there was no adhesion of any aquatic growth and no peeling from the adherent surface of the adhesive sheet.

Further, the primer liquid of the blending was applied on an FRP plate of 50 mm length x 125 mm width x3 mm thickness so that after drying, its application amountwould become 4to 6 g/M2 and after drying, 20 samples were prepared, on which test pieces of the adhesive sheet of the present invention of 25mm width were stuck, and these samples were immersed in saltwater of 3.5% concentration held atthe temperature of WC, and the change was investigated with the lapse of time. As a result, 180'peel adhesion after one month 30 was 7.6 kg/25mm and there was almost no change.

Comparative example 1:

FRP plate of length 30Omm xwidth 21 Omm xthickness 3mm was suspended at 1 m underthe water level of seawaterfor one year in the same way as Example 1, and the condition of adhesion of aquatic growthswas 35 observed, resulting in that after one year, remarkable adhesion of barnacles and seaweed wasfound.

Example2:

Similarto Example 1, a primer liquid was applied on the surface of a copperplate of 40Omm width x 1 Orn length x 0. 1 mm thickness to form a similar primer layer, on which a similar pressure sensitive adhesive layer is 40 provided, to which layer a release paper was stuck to obtain an adhesive sheet for prevention against aquatic growths according to the present invention. Similarto Example 1, asto the obtained adhesive sheet, its peel adhesion, and condition of adhesion of aquatic growths were tested, of which the results were as follows.

Utterly no adhesion of aquatic growths due to leaving the adhesion sheet in seawaterfor one year wasfound.

180'peel adhesion to the FRP plate was 2.4 kg/25mrn and 180'peel adhesion to the primer processed FRP plate 45 was 7.6 kg/25mm, immersed in saltwater of 3.5% concentration at40T temperature, and 180'peel adhesion after one month was 7.4 kg/25mm, showing almost no change.

Comparative example 2:

An adhesive sheetwas made similarto those described in Example 1, exceptthe primer processing on the 50 surface of the base material of copper-nickel alloy plate. The thus obtained adhesive sheetto which primerwas not applied, was stuck on both the surface and back sides of the FRP plate of length 30Omm x width 21 Omm x thickness 3mm, the plate was suspended at 1 m underthe water level of seawater introduced in the laboratory of our company for one year like Example 1. The resultwas that on the surface side of FIRP plate, the adhesive sheetwas stuck hard and on this surface aquatic growths were not found, however, on the back side of the FRP, 55 the adhesive sheet had peeled off and on the surface of FIRP, barnacles and seaweeds were attached. And, 180' peel adhesion to FRP plate of adhesive sheetto which a primerwas not applied, after one month immersion in seawater of 3.5% concentration at 40'C temperature was in any case remarkably inferior relative to Example 1 and 2.

As mentioned above, the adhesive sheetfor prevention against aquatic growths according to the present 60 invention is excellent in the effect of prevention against adhesion of aquatic growths and almost no degradation of adhesion during lapse of long time in seawater, achieving adhesion performancewith excellent durability.

The present invention has the above mentioned formation, and may be easily stuckon a surface in contact with water of steel plate ships, wooden ships, reinforced plastic ships, ferrocement ships and other ships and 65 4 GB 2 179 271 A 4 yet no degradation due to oxidation of pressure sensitive adhesive copper or copper alloy plate maybe safely and surely held on the outside surface of the hu I I without failing off, and sticking and propagation of mussels, barnacles, seaweeds and other growths maybe prevented and as well the corrosion of the hu I I of, for example, steel plate and other structures underwater maybe prevented. This adhesive sheet has an excellent effect when applied to other than ships, for instance, steel piles used for quay wal Is, other iron materials, inside faces of seawater conduits for cooling in power plants, outside faces of these conduits always in contact with seawater,structures of seawater intake gates, for the purpose of preventing against adhesion of aquatic growths and corrosion.

Claims (6)

1. An adhesive sheetfor prevention against aquatic growths, wherein a primer layer is provided on one surface of copper-nickel alloy plate, with a weight ratio of copperto nickel of 100:0 to 80:20, on which primer layer a pressure sensitive adhesive layer is formed.

2. An adhesive sheetfor prevention against aquatic growths according to claim 1, wherein the pressure is sensitive adhesive layer contains natural rubber or synthetic rubber as elastomer, with which tackifier resin, filler, cross linking agent, auxiliary agent of cross linking and antioxidant are blended to form an adhesive of excellent antiaging property.

3. An adhesive sheetfor prevention against aquatic growths according to claim 1, wherein said primer layer is formed with one or more than two kinds of elastomers selected from modified natural rubber, styrene-budadiene rubber, nitrile rubber and chlorinated rubber, tackifier resin, epoxy resin and curing agent of epoxy resin.

4. An adhesive sheet for prevention against aquatic growths according to claim 1 or 3, wherein said primer layer is formed with 200 to 300 weight parts of tackifier resin, 30 to 200 weight parts of epoxy resin, epoxy equivalent of curing agentto 100 weight parts of elastomer.

5. An adhesive sheetfor prevention against aquatic growths according to claim 1, 3 or4, wherein said primer layer contains an anti-injurious agent of copper.

6. A method of sticking an adhesive sheetfor prevention against aquatic growths, characterized in that when an adhesive sheetfor prevention against aquatic growths, in which a primer layer is provided on the surface of copper-nickel alloy plate, on which a pressure sensitive adhesive layer is formed, is stuck on the 30 surface of the object on which aquatic growth isto be prevented, a primer layer of the same composition as said primer layer is provided on the surface of said object, on which said adhesive sheet is applied.

Amendments to the claims have been filed, and have the following effect:

(a) Claims 4 above have been deleted ortextually amended.

(b) New or textually amended claims have been filed as follows:- 4. An adhesive sheetfor prevention against aquatic growths according to claim 1 or3, wherein said primer layer is formed with 20 to 300 weight parts of tackifier resin, 30 to 200 weight parts of epoxy resin, epoxy equivalent of curing agent to 100 weight parts of elastomer.

Printed for Her Majesty's Stationery Office by Croydon Printing Company (L) K) Ltd, 1187, D8817356.

Published by The Patent Off[ce,25Southampton Buildings, London WC2AlAY, from which copies maybe obtained.

Z i